I request support through the K08 award to complete my transition from a clinical board-certified psychiatrist with prior research training in epidemiology to an independent translational researcher in genetic and environmental factors for smoking cessation. To achieve this goal, I need further training and experience in advanced genetics, cessation science, and longitudinal research methods, to enable me to conduct future prospective studies on genetics of smoking cessation. I will be guided by experts in the fields of advanced genetics (Drs. Laura Bierut, Alison Goate, John Rice, and Robi Mitra), cessation science (Drs. Timothy Baker and Gary Swan), and longitudinal research (Drs. Naomi Breslau, Eric Johnson, Laura Bierut, and Timothy Baker). The training goals will be advanced through the following proposed research on nicotine dependence which is a serious public health problem. Some genetic variants associated with nicotine dependence and smoking cessation have been identified with modern genetic methods, but account for only a small amount of genetic variance. Our preliminary results suggest comprehensive nicotine dependence phenotypes and prospective cessation measures have greater sensitivity to detect genetic associations. This study aims to fill gaps in the research literature by conducting (1) Genome Wide Association Study (GWAS) analyses of nicotine dependence using comprehensive novel phenotypes in two existing, complementary datasets (population vs. treatment sample), (2) GWAS analyses of prospective smoking cessation phenotype, and (3) a pilot longitudinal follow up study of nicotine dependence subjects to replicate the genetic findings of smoking cessation from study aim 2, and to examine identified genetic risks jointly with environmental, comorbid, and treatment factors. We hope to uncover novel genetic variants associated with refined phenotypic characteristics of nicotine dependence and smoking cessation. Genetic risks associated with smoking cessation may be different from those for nicotine dependence, and this distinction will be useful in translating genetic risk to outcome research. Knowledge of how genetic risks influence clinical outcomes and whether they are modified by treatment and comorbid disorder factors will not only clarify the etiology of nicotine dependence to create opportunity for prevention, but also provide needed evidence for individualized cessation treatments to increase the probability of successful quitting. This will be the foundation for future R01 applications for large scale, prospective studies of smoking cessation trials. In summary, by the end of this award, I will become an expert in psychiatric genetics with a focus on smoking cessation. Through my training in advanced genetic methods, cessation science, and longitudinal analyses, along with hands on experience in longitudinal data collection and analyses, I will establish a unique smoking cessation research program at Washington University and launch an independent career conducting large scale smoking cessation trials that will make important contributions to the treatment of nicotine dependence and related disorders.